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    SubjectRe: PCIE
    Roland Dreier wrote:
    > > I am now wondering whether the usage of MSI would help in this case and
    > > that i should be using enable_msi before request_irq ?
    > MSI interrupts are never shared. So if pci_enable_msi() succeeds, you
    > can be sure that the interrupts you get with that IRQ number are
    > coming from your device.

    i presume then i shouldn't be using IRQF_SHARED, if using MSI.

    Another question would be if the device supports multiple messages, MSIX
    should be used ?
    In such a context, if i request for say more than the messages that i
    need, say i request 16 messages, but use only 1 or 2, that does bear any
    consequences ?

    > But using MSI does not work on all systems, so your driver needs to
    > work with standard (possibly shared) INTx interrupts too. And you
    > should probably provide at least a module flag to disable the use of
    > MSI, to avoid problems on buggy systems.

    I should probably look for CONFIG_PCI_MSI and check whether the system
    supports MSI pci_enable_msi() ?

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      Last update: 2007-05-26 17:09    [W:0.024 / U:20.788 seconds]
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